Abstract
Background: Young people spend hours on social media every day, where following influencers is the norm. Influencers post frequently about alcohol and alcohol brands and there has been a rise in influencer marketing. However, prevalence estimates rely on manual analyses of only a small number of posts. We used a large language model (LLM) to estimate at scale how often top Australian Instagram influencers reference alcohol and alcohol brands, and whether this varies by influencer type.Methods: We identified 988 of the most-followed Australian Instagram influencers and retrieved all 667,531 of their posts that were visible to all users, including those under 18 (i.e., not age gated). An LLM classified whether each post referenced alcohol and these were screened manually to record brand references. Influencers were coded into 14 types (e.g., athletes, actors).Results: Most influencers (87.45%) referenced alcohol and 47.10% referenced an alcohol brand in at least one post. Overall, 20,448 posts (3.06%) referenced alcohol and 2,869 (0.43%) a brand (14% of alcohol-related posts). Food influencers posted the most alcohol and brand-related content, while athletes posted the least alcohol-related content but had the highest proportion referencing a brand.Conclusions: Influencer alcohol-related and alcohol-related brand content is pervasive on Instagram and reaches audiences of every age, including those under 18 who should not see alcohol advertising.So what: Given the link between exposure and use, health promotion should aim policies and strategies at reducing alcohol-related content, particularly branded content that likely reflects influencer marketing.